title: Study of an ethylene oxide-terminated bent-core compound: synthesis and Langmuir-Blodgett film structure.
abstract: Bent-core compounds have attracted interest due to their unusual supramolecular structures, uncommon physical properties such as ferro- and antiferroelectricity and potential applications in fields such as nonlinear optics. Their incorporation into nanostructured materials, however, needs to be improved in terms of accurate control of the packing and orientation of the molecules in practical structures. Here, we have synthesized a novel bent-core compound bearing a tetraethylene glycol (TEG) chain as the hydrophilic head group and studied its capacity to obtain monomolecular films by means of the Langmuir-Blodgett technique. We developed a synthetic route to the material and studied its behavior in Langmuir and Langmuir-Blodgett films by means of a variety of characterization techniques, including a new model for the interpretation of UV-Vis reflection spectra of bent-core compounds. We found that the new head group, while destroying the formation of bulk mesophases, stabilizes the formation of the monolayer at the air-water interface and allows core-core interactions to dominate film dynamics, thus providing a promising alternative to carboxylic acid head groups.
authors.affiliation: Departamento de Química Física, Facultad de Ciencias, Universidad de Zaragoza, 50009 Zaragoza, Spain.
authors.forename: Víctor
authors.initials: V
authors.lastname: Pérez-Gregorio
authors.forename: Miguel
authors.initials: M
authors.lastname: Cano
authors.forename: Ignacio
authors.initials: I
authors.lastname: Gascón
authors.forename: Nélida
authors.initials: N
authors.lastname: Gimeno
authors.forename: M Blanca
authors.initials: MB
authors.lastname: Ros
authors.forename: M Carmen
authors.initials: MC
authors.lastname: López
keywords: Bent–core compounds; Ethylene oxide chain; Langmuir and Langmuir–Blodgett films; Reflection spectroscopy of Langmuir films